Chair.



No. 885,843. PATENTED APR. 281908. C. W, FISCHER, C. ZIMMERMAN & E. G. WALKER.

CHAIR.

/M a IWTHA AHM APPLICATION FILED MAR.17, 1905.

Ill/ll UNITED sTATEs PATENT oEEioE.

CHARLES W. FISCHER, CHARLES ZIMMERMAN, AND EDWARD (j. WALKER, OF CHICAGO, ILLI- NOIS, ASSIGNORS TO THEO. A. KOCHS COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

CHAIR.

Specification of Letters Patent.

Patented April 28, 1908.

Application filed March 17, 1905. Serial No. $350,631.

To all rz chom it 'may concern:

Be 1t .known that we, CHARLES W. FISCHER, CHARLES ZIMMERMAN, and ED- WARD C. WALKER, citizens of the Unitedy nown as barbers or dental chairs, in which mechanism is provided for raising and lowering the chainseat which is arranged to rotate on a suitable base. Our present improvements have to do with such chairs inwhi'ch the chair seat is raised and lowered by fluid pressure,-.such, for example, as that illustrated and described in the pending applicati'on of Charles W. Fischer and Charles Zimmerman, No. 199,073, filed March 21, 1904, in which the chair seat is raised by pum ing oil into a plunger cylinder in which the p unger which carries the chair seat moves. In such prior constructions the Weight of the chair, when elevated, usuallyvis sustained by the fluid in the lunger chamber,-tl1e iluid being held therein by a check valve. While this construction is to a certain extent efficient and satisfactory, We have found that it is desirable that further means be provided for more positively locking the chair in its elevated position so that even if there should be more or less leakage around the check valve the chair may be held in its elevated osition, and to provide such additional ocking means is oneof the principal objects of our invention.

A further object is to provide improved means for locking the chair seat against rotation.

These obj ectswe accomplish as illustrated in the drawings and as hereinafter described.

What we regard as new is set forth in the claims.

In the accompanyin draWings,-Figure 1 is a vertical section o the base of a chair, showing also vthe plunger, parts of which are also in section; Fig. 2 is a sectional detail of the upper portion of the base, the plunger being removed; Fie. 3 is a plan View of the lookin sleeve; and Fig. 4' is an elevation thereo ,l art being broken away. @Referring to the draWings,-5 indicates the plunger of the chair, which carries a seatsupport 6.

7 indicates a shell, referably of cast-iron, which is provided with a plunger-chamber 8, and a piston-chamber 9, arranged side by side, as shown in Fig. 1. The plungerchamber 8 receives the plunger 5, while the piston-chamber 9 receives a piston 1.0 carried at the end of a iston-rod 1l. The pistonrod is connecte at its upper end with a cross-head -12 mounted on suitable' pivots 13 which are journaled at the top of the casting 7, at opposite sides of the upper end of the lunger-chamber 8, as illustrated in Fi 2,-

m which 14 indicates one of the blocks W ich carry the bearings for the pivots 13. The

'cross-head 12 is in the form of a collar having projecting lugs 15-16, and embraces the plunger 5, as shown in Fig. 1.

17 indicates a foot-lever fulcrumed at 18. Said lever is connected by a rod 19 with the lug 16, so that by operating the foot-lever the piston 10 may be reciprocated.

2O indicates a s ring mounted on the rod 19 for normally ho ding thelever 17 in its uppermost position.

As shown at 21 in Fig. l'the up er of the piston chamber 9 is enlargedp to oil-reservoir.

.22 indicates a passage connecting the piston-chamber 9 and plunger chamber 8 at their lower ends.

23 indicates a check valve in the lower portion of the piston-chamber 9 for preventing the return of the oil thereinto from the plunger-chamber.v

The construction and operation of the parts. thus far described are all set forth in the application of Fischer and Zimmerman, above referred to; and as the details of such construction have nothing to do with our present invention they will not be described more in detail herein. It is sufiicientto say ortion orm an that by operating the foot-lever 17 oil is the reservoir 21,-consequently lowering the chair seat.

l For the' purpose of positively lockingthe plunger against downward movement whenever 1t is raised, and also for locking the chair against rotation, we provide a split sleeve 24 having a peripheral flange 25 at its upper end. The inner surface of the sleeve 24 1s of uniform diameter, but it tapers gradually inv thickness towards its lower ed e Where'it is thinnest. Said sleeve, when lts split ends are in contact, is slightly less in diameter thany the plun er, so that it may be caused to closely gri tte plunger, as hereinafter described. Xs shown in Figs. 1 and 2, said sleeve is iitted in to the upper end of the een tral portion of the shell 7 which forms the plunger-chamber 8 and .which is suitably tapered to receive it, the flange 25 projecting over-the top of the shell 7, as shown.

The sleeve 24 is made of cast-iron, or other' suitable material,l suliciently elastic to permit of the necessary contraction and expansion.A The sleeve 24 normali 4binds on the plunger closely enough so t at it is lifted slightly when the plunger is. forced up and in order to press the sleeve 24 down into operative osition, one or :more pins 26 are provided) in the cross-head 12,-preferably one adjacent to each pivot 13,-Which pins are made in the form of screws so as to be adjustable toward and from the flange 25 onchamber below the plun er, also carries the pins 26 away from the s eeve 24, it Will be apparent that said sleeve may rise slightly with the plunger, but the return stroke of the lever 17 carries the pins 2.6 again into engagement with the sleeve forcing it down closely into operativeiengagement with the lunger. The result is that the plunger is locke against reverse movement during each return stroke of the o erating lever, thus preventing the plunger omsettling back, `to an appreciable extent, u pon such return stro e, as usually occurs with constructions heretofore in use. When the plunger is to be lowered, the

lever 17 is depressed to its lowermost point,

and the pins 26 are thereb held out of enga ement with the sleeve 4, which accord:-

lng y is not forced dow'n closely into contact `w1ththe plunger,.--Which may accordingly descend. Furthermore', when the sleeve 24 is inoperative position, b reason of its frictional engagement with t e shell 7, it locks the1 plunger and seat against rotation.

27l indicates' an adjustable stop-prefer`- ably a screw-which is tted in the upper end of the shell 7 and passes through a suitable' hole in the flange 25 above which it proj ects,. underlies theI as shown in Fig. '2. Said stop cross head 12l at the opposite side of the pivot 13 from the pins 26-'preferably adjacent to the piston-rod 11, as shown, ,and serves to prevent the cross head 412 Jfrom striking the ilange 25 and forcing the sleeve 24 down'while the plunger is risin' Having thus described speciiicay the embodiment of our invention illustrated in the accompanying drawings, we Wish to be understood that our invention is not restricted to such particularconstruction,but includes generica claims. Moreover, while our invention is designed primarily to be applied to chairs having fluid-pressure mechanism for raising the seat, it`maybe applied to any other oonstruction to which it is adapted, and, indeed, may also be applied to other devices than chairs. Furthermoreowing to the fact that the locking device is ositively moved into operative position, and) does not depend upon gravity, it may be ap -lied to plungers, or eclluivalent devices, Ywli p anes thanthe vertical, and it should be understood, therefore, that the terms elevating and descending or synonymous ich move in other' ly the subject-matter of the broader terms herein employed, are to be construed l accordingly,

That wh'ch We claim as our invention and Vdesire-to secure by Letters Patent is,

1. y'-lhe combination of -a plunger, a chamber in lwhich said plunger moves, means for elevating said plunger, andia split sleeve at the upper end of said chamber andA surrounding'said lunger, 'said sleeveV being actuated by said p unger elevating mechanism to lock Ithe plunger a ainst descent. 1

2. The com ination of a-plunger, a charnber in which said plunger moves, a; crosshead, a lever connectedwith one arm ?of said cross-head, means connected with the other arm of said cross-head for raisingv the lun.

cross-head, means connected with the other arm of said cross-head for raising the lun ger, anda split sleeve at the upper end o said chamber surrounding said plunger, said cross-head having adjustable means adapted j to depress said split sleeve on each alternate stroke of the lever.

4. The combination of a plunger, a pluri 'ger chamber, a split sleeve at the upper end of said -plunger chamber surroun mg said lunger, and lever actuated mechanism for orcing fluid into said plunger chamber beloW the plunger and operating to move s-aid sleeve into operative engagement with the plunger.

5. The combination of a plunger, a plunger chamber, a split sleeve at the u per end of said plunger chamber surroun ing said lunger, and lever actuated mechanism for orcin fluid into said plunger chamber below the p unger and operating to move said sleeve into operative engagement with the plunger at each alternate stroke of the lever.

6. The combination of a lunger, a plunger chamber, means adapted to engage said plunger to lock it at any point against descent, a lever, means actuated bythe move# ment of said lever in one direction for forcing liquid below said plunger to elevate the same and a spring adapted to move said lever in the opposite direction for moving said locklng means into operative engagement with the plunger. y 7. The combination of a plunger, a plunger chamber, a split sleeve mounted on said plunger at the upper portion of said plunger chamber, a rocking crosshead adjacent to said split sleeve, a lever for rocking said crosshead, means connected with said cross-head 4for forcing liquid into said plunger chamber below the plunger, and means carried by the cross-head for moving said split 'sleeve into operative engagement with the plunger.

8. The combination of a plunger, a plunger chamber, a split sleeve mounted on said plunger at the upper portion of said plunger chamber, a rocking crosshead adjacent 'to said split sleeve, a leverforrocking said crosshead, means connected With said cross-head for forcing li uid into said plunger chamber below the cross-head or moving said split sleeve into o erative engagement with the plunger when t e lever is raised, and a stop for (preventin the engagement vof said cross-hea with sai sleeve when the lever is depressed.

9. The combination of a plunger, a s lit Sleeve embracing said lunger, a suit'a le support in which said pllunger moves, said support havin a socket adapted to receive sai sleeve an force the same into locking engagement with said plunger, fluid-pressure mechanism for elevatln the plunger, and

means for moving said s eeve into operative unger, means carried by the engagement with said plun er between successive strokes of said flui -pressure mechanism.

10. The combination of a plunger, a chamber in Which said plunger moves, a lever provided With means for elevating said plunger, a split sleeve surrounding said plunger, and a spring adapted to actuate sald lever When t e lever is released to cause said split sleeve to operatively engage said plunger to lock it against descent.

11. The combination of pump mechanism comprising a chairsupportin plunger, a lever, means actuated by said lever for elevating the plunger, and a chamber in which said plunger moves, a Wedge for engaging said plunger to lock it against descent, and means positively actuated by the pump mechanism for moving said Wedge to cause it to lock said plunger against descent when said lever vis released.l V 4 12. The combination .of pump mechanism comprising a chair-supportinor plunger, a lever, means actuated by said tlever for elevating said plunger, and a chamber in which said plunger moves, a split sleeve surrounding said plunger and means positively actuated b said pump mechanism for causing said sp it sleeve to engage said plunger to lock it against descent when said lever is released.

13. The combination of a plunger, a plunger chamber, means adapted to engage said plunger to lock it against descent, alever, a spring adapted to move said lever in one direction for moving said locking means into operative enga ement with the plunger, and

means actuate by the movement of said lever in the other direction for elevating the plunger and releasing said locking means. 14. The combination of a plunger, a plunger chamber, a lever, means positively actuated by the movement of said lever in one direction to the limit of its motion for locking said plunger against descent, means actuated by the movement of said lever in the other direction for elevating the plunger, and a spring normally holding said' lever in its plungerlocking position. l i

CHARLES W. FISCHER. CHARLES ZIMMERMAN. EDWARD C. WALKER. Witnesses:

Roar. T. KocHs, HENRY HAND. 

